Art of petroleum distillation.



E. M. CLARK. ART OF PETROLEUM DISTILLATION. I

. APPLICATION FILED, Q-OT. 24. 1914.

Patented Mar. 16, 1915.

2 SHEETSSHEET l.

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E. M. CLARK.

ART OF PETROLEUM DISTILLATION. APPLICATION FILED OCT. 24, 1914,

Patented Mar. 16, 1915.

2 SHEETSSHEET 2.

, To all wizom it may concern .Be it known that I, EDGAR citizen of the United States, residing at Ali 'IE ST EDGAR M. 01331:, or imm' mms, .n ssrenon, 'ro STANDARD on. comm, or wnrrme, INDIANA, a conroaa'rron or INDIANA.

' ART OF PETROIiEUM DISTILLATION.

v Specification of Letters Patent.

Patented Mai-.16, 19115.

Original application filed April 20, 1914, Serial No. 883 244. Divided and. this application filed October 24., r 1914. Serial No. 868,362.

M. CLARK: a

ton, in the, county of Madison and State of Illinois, have invented a new and useful Improvement in the Art of Petroleum Distillation, of which the following is a specification.

In the art of distilling residue of petroleum distillation, such' as gas oil or fuel oil,

at atmospheric pressure, vaporization begins at a temperature of about 250 F., and all will distil over at a temperature upward of 650 F. In distilling this residue under a pressure upward of three atmospheres, producing a range of temperature of about 650 F; to 850 F., according to the inventions of Letters Patent No. 1,049,667, granted January I, 1913, to W. M. Burton, a material quantity of fixed gas (amounting to about 2 per cent. of the stock charged into the still) is produced.

In the practical'application of the process of the aforesaid patent, a battery of stills (usually ten or more) is used. Each still is provided with its own condenser and with further separate "equipment involving a drum for receiving the products of the condenser and separating the water and gas controlling the rate of discharge.

- the receiving drum. As the distillation proceeds small quantitiesof uncondensed vapor or gas collect in the apparatus, and after a material quantity of low grade distillate upward of about 8 per. cent. of the stockcharged) has been produced,isuflicient gas has collected in the apparatus to create -a pzresspreof vapors through the condenser.

ontini edfiring of the still raises further the temperature of the contents producing increasing formation of gas and building up of pressure in the apparatus. When the desired temperature (about 650 F.) and pressure (say about 70 to 75 lbs.) have been attained, the gas in the apparatus is allowed to escape slowly through a valve in its discharge l1ne from the top of the receiving drum. Vapors will then begin to come over' tion process is necessarily slow, the formation of gas is very gradual. Production of the high-grade distillate is dependent on constant pressure on the apparatus. A slight drop in pressure causes the vapors to come over more freely and produces lowgrade distillate, and, conversely, even a slight increase in pressure entirely stops the flow of vapors with resultant danger to the apparatus. 1 It is the primary purpose of the present invention to provide a process for controlling the discharge of gas and liquefied distillate so that a minimum amount of the latter of lowv grade and a maximumamount thereof of high grade shall be produced. It is a further purpose to provide, a method of safeguarding the apparatus used by preventing any extraordinary excess of pressure therein, and also to so apply a gaspressure of about 70 to '75 lbs. from stills in the battery that are running to the contents of a still when freshly charged as to prevent distillation of such contents before the desired temperature has been attained.

rying out my improved process. The apparatus illustrated, however, forms no part of the present invention, such apparatus forming the subject matter of the claims in my copending application No. 833,244, filed April 20, 1914, of which this application is a division. i In the drawings, Figure 1 illustrates diaammatically, by a plan view, a battery of stills and the equipment that belongs with them for practising the invention, and Fig.

2 isa view in sectional elevation, the section being taken on line 2, Fig. 1.. 7

Four stills 1, denoted respectively A, B, C and. D, are indicated by dotted representation and will s uflice for the purp oses of the explanation hereinafter given. These stills are shown under a shed 2, between walls 3, and they communicate with a stack .L'common to all, for carrying ofi products of combustion from the furnaces under the stills,

one of these furnaces being represented at 1 through the inner wall 3 of a housing, of

which the sidewalls 3 are shown, a pipe 7 for conducting the products of the condenser, composed of liquefied distillates and the light," gaseous products of distillation which have not yielded to the action of the condenser, into a separate drum 8 at the top of the latter. From the bottom of each drum leads a pipe '9 containing a'meter 10 for measuring the liquefied distillate and hav-' ing two valved-branches 10 and 10 which discharge, respectively, into header-pipes 11 and 12 closed at one end and containing similar shut-off valves 13 and 13 respectively. These header-pipes discharge to storage-tanks (not shown). Each drum discharges gas from its upper end through a pipe 14 having two valvedbranche's 1 1? and 14 leading, respectively, into header-pipes 16 and 17, which are closed at one end and contain similar shut-0E valves 18 and 18 respectively, these pipes which also' 'lead to storage-tanks (not shown), being connected by a pipe 19 containing a pressure relief valve 20 of;any ordinary or suitable type.-

At 21 is shown, leading from' the bottom of each drum to a gutter 22, a valved pipe for drawing off the Watery product of condensation of the vapors generated in the early part ofthe run,

For the purposeof explanation, let it be assumed that three .of the stills 1, namely those denoted as A, B, and C, are running at the cracking temperature ofupward of 650 Rand under a pressure of about to 7 5 lbs; of the gases on the contents of the stills. The valves inbranches 14: connected with these three stills are open and the gases are. discharging into the headerpipe 17 and are being held back by the partlyclosed valve 18 in the latter and the relief valve 20, to produce the required pressure of 70 to lbs. in thatheader-pipe and throughout the apparatus of the running stills. The valves in the pipes 21 belonging to these three stills are closed, since all Watery vapor from them has been distilled off before they reached the cracking temperature.- The valves in branches 1O are open and high-grade liquefied distillate is being discharged from the bottoms of the three respective condensers through 1e meters into the header-pipe 12 and through its partly open valve 13 to storage. The rate of this discharge is regulated by the valve 13 inthe header-pipe 12 to maintain the required pressure throughout the apparatus and discharge the distillate as it is produced The three stills thus running are all subject to the same pressure y -reason of the valves in;branches 14* leading to the headerpipe 17 and the valves. branches 10 leading to the header-pipe 12 being open. These stills being connected by the header-pipes 17 and 12, give a sufiicient volume of gas and liquid distillate to make the rate of their discharge easily controllable by the valves 18 and 13'. a

Let it also, be assumed that the fourth still, denoted as D, has just been ,freshly charged and fired. The valve in pipe 21 and .the valves in branches 10, 10 and 14*,

belonging to that still are closed, and the corresponding valve in branch-14 is opened.

The still D is thus closed tothe 70 to 75 lbs.

pressure maintained in the header-pipes 12 and 17, and is open only to the header-pipe 16, which conducts the gases to storage, or'

to the fur ces. The firing of this still is cont nued 'ith resultant rise of temperature of its contents. At about 212 F. the watery portions of these contents are driven over through the respective condenser 6 into the drum communicating therewith. From time to time the valve in the respective pipe 21 is opened to discharge the water into the gutter 22. When the water has all been 'driven off,

which is indicated by the temperature of the contents of the still D, the oil portion thereof will begin to distil over at about 250 F.

To stop this distillation and the resultant production-of low-grade distillate, the valve 'in the branch 14 belonging to the still D is closed and that in the corresponding branch 14' is gradually opened. This allows the gas from the three other stills, that are running under a pressure of 70 to 75 lbs. in the header-pipe 17, to exert its pressure back through the branch 14?,belonging to still D,

and the interposed equipmentupon the contents of that still to stop the flow of vapors from the latter.- In this way the pressure upon the contents of the freshly-charged still is raised to that upon the stills A, B.

and C. The-firing of still D is continued until the temperature of its contents is raised to upward of 650 F., when that still will begin to drive over its gases through the,

condenser, and drum and branch 14 belonging to it, into the header-pipe 17, and the production of high-grade liquefied distillate I i will begin. The valve in branch 10 is now opened and the high-grade distillate produced discharges into the header-pipe 12 in connection- -with that produced from the other running stills. The four stills are now running in conjunction, all subject to the same control and the same pressure-in fiuences. The sudden generation of excessive or dangerous pressure in one still is prevented by the connection of all through the header-pipes and open valves.

Let it further be presumed that a still, say that denoted A, has completed its run and. is ready to bedrawn ofi, cleaned and freshly charged. Itsfurnace-fire is drawn, and the valves in branches 10 and 14: are closed thereby shutting it off from the 70 to 75 lbs. pressure in'the header-pipes l7 and 12 and from the influence of the stills B, C and l). The valve in the respective branch 14: is slowly opened to permit the gas to pass through the header-pipe 16 to storage or to the furnaces; and the valve in branch 10* is also opened, to permit the low gradeor inferior liquefied distillate produced after closing 01f the header-pipe 17, to, pass through the header-pipe 11 to storage. As soon as the gas that was held under 70 to 7 5 lbs. pressure in the equipment belonging to still A has been discharged, the tar or residual contents of the still are drawn 0E,

, and it is made readyto clean and receive a fresh charge. As will be understood each still in a battery is handled in this way after completing its run. I

I realize that considerable variation is possible in the detailed process thus specifically described, and I do not intend by'giving as an illustrative example a minutely defined process as carried out by the use of a preferred apparatus, to limit my invention thereto, my intention being, in the following claims, to claim protection upon all the novelty there may be in my invention, as broadly as the state of the art will permit.

What I claim as new and desire to secure by Letters Patent is:

1. In the art of treating liquid portions of the paraflin series of petroleum distillation having a boiling point of upward of 500 F. to obtain therefrom low boiling point products of the same series, the process which consists in heating the body of liquid material to drive ofl any contained water, then raising the temperature to a point at which cracking takes place, exerting and maintaining on the liquid body during such rise in temperature a pressure of the distillate of the same material in an advanced stage of distillation, whereby fractional distillation is prevented, and then proceeding with the cracking and distillation of the liquid body at such elevated temperature and under the pressure of the distilled material.

2. In the art of treating liquid portions of the parafin series of petroleum distillation having a boiling point of upward of 500 F. to obtain therefrom low boiling point products of the same series, the process which consists in heating the body of liquid material to the desired cracking temperature, then proceeding with cracking and distillation at such temperature, exerting and maintaining on the liquid body during its rise in temperature from the boiling point or its lightest oil constituents a pressure of incondensable gases produced by advanced distillation of the same material.

3. In the art of treating liquid portions of the parafiin series of petroleum distillation having a boiling point of upward of 500 F. to obtain therefrom low boiling point products of the same series, the process which consists in heating the body of liquid material to the desired cracking temperature, then proceeding with cracking and distillation at such temperature, exerting and maintaining on the liquid body .during its rise in temperature from the rality of stills, which consists in raising the temperature of one still to the desired cracking and distillation point, then proceeding with racking and distillation at such temperature, exerting and maintaining on the liquid body in this still, during such rise in temperature and during the subsequent cracking and distillation, a pressure of incondensable gases produced by advanlced distillation and cracking in another stil EDGAR M. CLARK. In presence o f A. K. Wm'mmw,

A. P. MCCORMICK. 

